The invention relates to a coupling valve for hydraulic lines.
Devices for coupling hydraulic lines are used, for example, in vehicles such as tractors, to provide a hydraulic connection between a hydraulic drive of an attached implement and a pressure means source on the side of the vehicle. Generally, to carry this out, several coupling muffs are provided on the side of the vehicle. The muffs are arranged at a small distance to each other at the rear of a tractor due to space limitations. Such coupling muffs are standardized and are formed to couple hydraulic connectors. The connectors are also standardized with respect to their dimensions by ISO 5675. The coupling muffs are provided as quick-connection muffs, but also can be formed as threadable muffs.
To insert, for example, a hydraulic connector, arranged at one end of a hydraulic hose, which leads to the implement-side hydraulic user into the vehicle-side hydraulic muff, opening of the coupling muff-sided as well as the hydraulic connector-sided valves is carried out, to provide a hydraulic connection. There are implements, in which the implement-side hydraulic devices still are under pressure after separation from the vehicle-side hydraulic supply. Thus, the coupling-in of the hydraulic connector by hand is nearly impossible even when the vehicle-side hydraulic supply is switched to a non-pressurized state. While coupling-in the projections of the cone valves of the muff and of the hydraulic connector abut each other and with further axial movement of the coupling muff and the hydraulic connector are displaced deeper into them, so that both valves are opened.
U.S. Pat. No. 4,672,998 relates to a connection arrangement with a coupling connector and a coupling muff, each having a valve. The coupling connector and the coupling muff are connected to each other by a rotary joint. In order to protect against damage, easy adjustment of the parts relative to the connected hose should be possible. Furthermore, while connecting the tools, the handling of the tools should be made easier by the larger space of movement. The opening of the respective valves takes place during the coupling-in process. If the system is pressurized, the coupling-in process takes place against the system pressure in this embodiment to provide the above described disadvantages.
Furthermore, coupling muffs are known, in which first the connecting process between the hydraulic connector and the coupling muff is carried out. Next, the opening of the connector valve is carried out by means of opening the muff valve by means of an actuating mechanism, which comprises an actuating lever. Such coupling muffs are described in DE 43 18 840 C2 or in U.S. Pat. No. 5,316,033, the specifications of which are incorporated by reference herein. Such switchable coupling muffs have, compared to the above described couplings, where the coupling-in takes place at the same time as the opening of the connector valve and of the muff valve, the advantage, that the valves will be opened by operating a lever by hand after having carried out the coupling process. Accordingly, coupling muffs and hydraulic connectors, which are under pressure, can be connected and their valves easily opened.
Because of the limited available space in vehicles, especially in tractors, normal coupling muffs can often not be replaced in general. Furthermore, in some implements the hydraulic connectors and the normal coupling muffs are easily coupled as they are not under pressure.
DE 196 47 936 A1 describes a fittings set for emptying, filling and/or airing of water parts of heating devices, e.g. gas boilers. Besides a manometer, a hand locking valve or such are connectable into a hose line by means of quick couplings (quick release couplings).